CROSS-REFERENCE APPLICATION
[0001] This application claims the benefit of provisional application Serial No.
62/018,262 filed June 27, 2014, which is hereby incorporated by reference in its entirety.
FIELD
[0002] The present invention relates to compositions, devices, kits and procedures for the
attachment of stent-containing medical devices to tissue.
BACKGROUND
[0003] A stent is a small mesh tube that is used to treat narrowed or weak lumens (e.g.,
an artery, vein, bile duct, esophagus, intestine, lung, etc.), for example, to counteract
lumen constriction due to various diseases and conditions. Stents can be formed from
metals, polymers or other suitable material. Stents can be biostable or bioresorbable,
drug eluting or non-drug-eluting. The most common use for a stent is in coronary arteries.
Other common types of stents besides coronary stents include peripheral stents, ureteral
stents (e.g., to ensure patency of the ureter), biliary stents (e.g., to treat obstruction
in the bile or pancreatic duct), esophageal stents (e.g., to treat blockages of the
esophagus), enteral stents (e.g., to treat blockage of the small bowel or colon),
and airway stents (e.g., to treat blockage of the trachea or bronchi), among others.
[0004] In some cases, stents are covered. If the covering of the covered stent is porous,
typically for use in the vasculature, it is often called a stent-graft. Stent-grafts
are used in the treatment of abdominal aortic aneurysms and weakened peripheral arteries.
Other covered stents may be used for the treatment of malignant or benign strictures
of the esophagus as well leaks and/or perforations in various body lumens, among other
uses. In some cases covered stents are temporarily placed and are removable.
[0005] Fixation is extremely important in the placement of a stent, whether covered, partially
covered or non-covered, because if the implant migrates, the treatment can be compromised
and further complications can occur.
[0006] As one specific example, placement of covered self-expanding metal or polymer stents
has been the first choice for palliative therapy of unresectable esophageal cancer.
These stents are also highly effective for the management of benign (peptic, postsurgical,
corrosive) strictures, esophageal leaks, perforations and fistula. In most cases,
rapid relief of dysphagia and adequate oral intake of nutrients can be achieved. If
the stent migrates from the esophagus, such as into the stomach or small intestine
causing an obstruction, the patient can suffer severe pain and fever resulting in
an additional surgery to remove the stent. The same also applies for other GI and
airway stents.
[0007] As another specific example, abdominal aortic aneurysm (AAA) stent-grafts are often
used to address arterial aneurysms, which are characterized by a weak artery wall.
Over time, blood pressure and other factors can cause this weak area to bulge like
a balloon and it can eventually enlarge and rupture. The AAA stent graft is designed
to seal tightly with the artery above and below the aneurysm. The graft is stronger
than the weakened artery and it allows blood to pass through it without pushing on
the bulge. If the stent-graft were to migrate, the seal above the aneurysm may be
compromised. This may result in blood flowing into the aneurysmal sac causing it to
grow and possible rupture. Re-intervention may be required.
SUMMARY
[0008] In accordance with some aspects of the present disclosure, stent-containing devices
are provided which comprise an associated bonding material, wherein the stent-containing
device is configured to bond to a lumen when exposed to an energy source while the
stent-containing device is in contact with the lumen.
[0009] In some aspects, the present disclosure features medical devices comprising (a) a
stent component, (b) an optional covering material, and (c) a bonding material associated
with the stent component, the optional covering material, or both; wherein the medical
device is configured to be implanted a patient and to bond to adjacent patient tissue
when the bonding material is exposed to energy from an energy source.
[0010] In certain embodiments, which may be used in combination with any of the above aspects,
the bonding material comprises a tissue solder material, the bonding material comprises
a tissue solder and a photosensitizing dye, or the bonding material comprises a tissue
solder and an energy absorber.
[0011] In certain embodiments, which may be used in combination with any of the above aspects
and embodiments, the bonding material comprises a tissue solder selected from chitosan,
albumin, collagen, elastin, fibrinogen, nano-peptides, derivatives of the foregoing,
and combinations of two or more of the foregoing.
[0012] In certain embodiments, which may be used in combination with any of the above aspects
and embodiments, the bonding material comprises a tissue solder and a photosensitizing
dye selected from rose bengal dye, methylene blue dye, fluorescein dye, indocyanine
green, basic fuchsin, fen, xanthane dye, riboflavin dye, lumichrome dye, flavin, lumiflavin
dye, Reactive Black 5 dye, and combinations of two or more of the foregoing.
[0013] In certain embodiments, which may be used in combination with any of the above aspects
and embodiments, the bonding material comprises a tissue solder and an energy absorber
selected from chromophores, superparamagnetic iron oxide nanoparticles (SPIONs), gold
nanorods, gold nanoshells, gold nanocages and combinations of two or more of the foregoing.
[0014] In certain embodiments, which may be used in combination with any of the above aspects
and embodiments, the bonding material comprises a tissue solder and a synthetic polymer
selected from polylactic acid, polyglycolic acid, poly(lactic acid-co-glycolic acid),
polydioxanone, polycaprolactone, and combinations of two or more of the foregoing.
[0015] In further aspects, which may be used in combination with any of the above aspects
and embodiments, the bonding material is associated with the medical device (a) by
a coating of the bonding material over at least a portion of the stent component,
the optional covering material, or both, (b) by integrating the bonding material into
at least a portion of the stent component, the optional covering material, or both,
or (c) a combination of the foregoing.
[0016] In further aspects, which may be used in combination with any of the above aspects
and embodiments, the bonding material is associated with the ends of the medical device
but not the center of the medical device or the bonding material is provided as a
series of bands or islands along the length of the medical device.
[0017] In further aspects, which may be used in combination with any of the above aspects
and embodiments, the medical device comprises the optional covering material. The
covering material may, for example, cover the entire stent component or cover only
a portion of the stent component. For instance, in certain embodiments, only the ends
of the stent component may be covered by the covering material, or the covering material
may be provided with a plurality of openings that provide areas where the stent component
is not covered by the covering material. In certain embodiments, the covering material
covers only a portion of the stent component, and the bonding material is associated
with the stent component in areas of the stent component not covered by the covering
material.
[0018] In further aspects, which may be used in combination with any of the above aspects
and embodiments, the medical device comprises the optional covering material, and
the covering material is sufficiently transparent to the energy from the energy source
such that bonding material that is positioned abluminally relative to the covering
material can be activated using an energy source positioned luminally relative to
the covering material.
[0019] Other aspects of the present disclosure provide methods of attaching a stent-containing
medical device to a lumen, wherein energy from an energy source is applied to a bonding
material that is associated with the stent-containing medical device, such that the
bonding material is activated and the stent-containing device is attached to the lumen.
In certain embodiments, stent-containing medical devices, such as those described
in any of the above aspects and embodiments, are employed in the method.
[0020] Yet other aspects of the present disclosure features kits that comprise any combination
of any two or more of the following items: (a) a stent-containing medical device comprising
a stent component, an optional covering, and an optional bonding material associated
the stent component, the optional covering, or both, (b) a bonding material in solid
form or in fluid form, (c) a surgical device, either with or without an associated
energy source, that is configured to receive and place the medical device in a subject,
(d) a guide wire, either with or without an associated energy source, or (e) a standalone
energy source. In certain embodiments, stent-containing medical devices, such as those
described in any of the above aspects and embodiments, are employed in the kit.
[0021] An advantage of the present disclosure is that compositions, devices, kits and procedures
are provided whereby stent-containing medical devices may be implanted in body lumens,
accompanied by bonding material activation, such that migration of the devices within
the body lumens is minimized or prevented after implantation.
[0022] Another advantage of the present disclosure is that compositions, devices, kits and
procedures are provided whereby stent-containing medical devices, particularly covered
stents, may be implanted in body lumens, accompanied by bonding material activation,
such that the devices are sealed with respect to the body lumens.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023]
Fig. 1 is a schematic illustration of a solder-containing stent, in accordance with
an embodiment of the present disclosure.
Fig. 2 is a schematic illustration of a solder-containing stent, in accordance with
another embodiment of the present disclosure.
Fig. 3 is a schematic illustration of a solder-containing stents in accordance with
another embodiment of the present disclosure.
Fig. 4 is a schematic illustration of a solder-containing stent, in accordance with
another embodiment of the present disclosure.
Fig. 5A is a schematic illustration of a solder-containing stent, in accordance with
another embodiment of the present disclosure.
Fig. 5B is a schematic illustration of a solder-containing stent, in accordance with
another embodiment of the present disclosure.
Fig. 6 is a schematic illustration of a solder-containing stent, in accordance with
another embodiment of the present disclosure.
Figs. 7A, 7B and 7C are schematic illustrations of a method of implanting a stent,
in accordance with an embodiment of the present disclosure.
Figs. 8A, 8B and 8C are schematic illustrations of a method of implanting a stent,
in accordance with another embodiment of the present disclosure.
Fig. 9 is a schematic illustration of a method of implanting a stent, in accordance
with yet another embodiment of the present disclosure.
Fig. 10 is a schematic illustration of an energy-emitting device, in accordance with
an embodiment of the present disclosure.
Fig. 11 is a schematic illustration of an energy-emitting device, in accordance with
another embodiment of the present disclosure.
Fig. 12 is a schematic illustration of an energy-emitting device, in accordance with
another embodiment of the present disclosure.
DETAILED DESCRIPTION
[0024] The present disclosure pertains to methods, compositions, devices and kits that are
useful in the implantation and fixation of stent-containing medical devices, for example,
bare stents, drug eluting stents, partially covered stents, and fully covered stents,
among others, in a body lumen of a subject, typically a vertebrate subject, and more
typically a mammalian subject, such as human subject, pet or livestock. The devices
may be implanted and fixed in a variety of lumens, for example, in a blood vessel
(e.g., artery, vein etc.), a lumen of the gastrointestinal tract (e.g., esophagus,
stomach, duodenum, small intestine, large intestine, colon, biliary duct, etc.), a
urogynecological lumen (e.g., ureter, urethra, fallopian tube, etc.), or an airway
lumen (e.g. trachea, bronchi, etc.), among other lumens, for instance, to prevent
migration within the lumen and/or create a seal with the lumen (e.g., in the case
of a covered stent). In various embodiments, stent-containing devices are used to
provide one or more of the following functions: support the patency of the body lumen,
strengthen the body lumen wall, seal the body lumen wall, and prevent tissue ingrowth
into the body lumen, among other functions.
[0025] According to one aspect, the present disclosure is directed to stent-containing devices
that are configured for implantation in a body lumen which comprise (a) a stent component,
(b) an optional covering material and (c) a bonding material. The bonding material
is associated with at least a portion of the stent-containing device (e.g., associated
with the stent component, the optional covering, or both), such that the stent-containing
devices are capable of bonding to adjacent patient tissue when exposed to an energy.
For example, the bonding material may be associated with the device by one or more
of the following strategies, among others: (a) the bonding material may be coated
onto all or a portion of the stent component, (b) the bonding material may be integrated
into all or a portion of the stent component, (c) the bonding material may be coated
onto all or a portion of the optional covering material or (d) the bonding material
may be integrated into all or a portion of the optional covering material.
[0026] The stent-containing device is introduced into a body lumen, for example, a blood
vessel, a lumen of the gastrointestinal tract, a urogynecological lumen, or an airway
lumen, among others, using a suitable procedure. Energy is then applied to the bonding
material such that that bonding material is activated and the stent-containing device
is attached to the body lumen tissue.
[0027] Different energy sources may be used for device attachment, depending on the mechanism
for tissue bonding that is employed. The energy source may be, for example, a source
of heat or light, such as a laser or a light-emitting diode (LED). Infrared and near-infrared
laser sources include carbon dioxide (COz), thulium-holmium-chromium, holmium, thulium,
and neodymium rare-earth-doped-garnets (THC:YAG, Ho:YAG, Tm:YAG, and Nd:YAG, respectively),
and gallium aluminum arsenide diode (GaAIAs) lasers, among others. Visible sources
include potassium-titanyl phosphate (KTP) frequency-doubled Nd:YAG, and argon lasers,
among others. Other energy sources include radiofrequency sources (e.g., a microwave
source), radiation sources (e.g., x-ray radiation, gamma radiation, etc.), or a locally
produced plasma. Argon plasmas are currently employed in various medical applications,
including argon beam coagulators, which ionize argon gas to form an argon plasma and
then use the plasma to deliver thermal energy to nearby tissue. In the present disclosure,
an argon beam may be used as a source of heat for tissue bonding.
[0028] In certain embodiments, the energy source is provided in a stand-alone unit. In other
embodiments, the energy source is combined with another device. For example, the energy
source may be combined with a delivery device, such as a guide wire or catheter.
[0029] In some embodiments, the energy source is connected to a control unit, which controls
the energy emitting from the energy source. Preferably, the amount of energy is sufficient
to activate the bonding material without significantly damaging the underlying tissue.
In some embodiments, the control unit is designed to accept user input (e.g., via
physical buttons, touchscreen, etc.), thereby allowing treatment parameters to be
set by a health care provider.
[0030] In some embodiments, the energy source is controlled without the use of a sensor
(e.g., based on the experience of the surgeon or based on a suitable energy output
algorithm). In other embodiments, a sensor is used in conjunction with the energy
source to provide feedback regarding the amount of energy being directed to the bonding
site, and this feedback can be used to adjust the energy source output. For example,
in certain embodiments, the sensor is a temperature sensor which detects the amount
of heat at the bonding site. In these embodiments, suitable software can be employed
to adjust the output of the energy source based on input from the temperature sensor.
The sensor may be provided, for example, in the same device as the energy source or
in a device that is different from the device containing the energy source. The sensor
may be provided, for example, in a medical device that is used for device delivery
(either with or without the energy source).
[0031] A variety of bonding materials can be used in conjunction with the present disclosure.
[0032] In this regard, laser tissue soldering processes are known in the surgical art whereby
tissue is bonded by applying a solder (commonly, a biological polymer) to the tissue,
after which a laser is used to activate the solder and form a bond. Without wishing
to be bound by theory, it has been reported that the mechanism of laser tissue soldering
appears to include a heating-induced protein denaturation-renaturation process. See,
e.g.,
B. Forer et al., Laryngoscope 116: June 2006, 1002-1006.
[0033] Solder materials are used in the present disclosure as bonding materials to bond
stent-containing device materials to tissue, for example, by the application of heat
to a solder material while it is in contact with a stent-containing device material
(e.g. a stent component material or an optional covering material) and tissue, such
that the stent-containing device material is bonded to the tissue. As indicated above,
beneficial energy sources for the application of heat include light sources (e.g.,
lasers, etc.), radiofrequency sources (e.g., microwave sources, etc.) and plasma sources
(e.g., argon beams, etc.), among others.
[0034] Particularly beneficial solder materials have a relatively low activation temperature
and are bioresorbable. For example, the solder may be bioresorbed over time, typically
between about 4 days and six months (e.g., ranging from 4 days to 1 week to 2 weeks
to 1 month to 2 months to 3 months to 6 months) (i.e., ranging between any two of
the preceding numerical values), depending on the solder that is used. The bioresorption
rate may be adjustable to provide bioresorption within this range, or to sooner than
or after this range, by adjusting the chemistry of the solder.
[0035] Specific solder materials for use in conjunction with the present disclosure include
solders of biological origin and synthetic solders. Examples of solders of biological
origin include those based on biological polymers, for example, polypeptides including
nano-peptides and proteins such as albumin, collagen, elastin, fibrin, fibrinogen,
thrombin, prothrombin protein derivatives, as well as polysaccharides including chitosan,
among others. In some embodiments, two, three, four or more solder materials such
as those described above are employed. Specific examples include a combination of
albumin and collagen, a combination of albumin and chitosan, a combination of collagen
and chitosan, and a combination of albumin, collagen, and chitosan, among many other
possible combinations.
[0036] Other polymers that may be added include: water soluble or bioresorbable polymers,
for example, synthetic water soluble or bioresorbable polymers, such as polylactic
acid, polyglycolic acid, polydioxanone, polycaprolactone, tyrosine based polyesters,
tyrosine based polycarbonates, polyesteramides, polyanhydrides, polyhydroxyalkanoates,
polyethylene glycols, polyorthoesters, pluronics, such as block copolymers of ethylene
glycol and propylene glycol, polyamides, polyvinylalcohol, hydroxyl substituted poly(meth)acrylates,
polyethylene glycol substituted (meth)acrylates, (methacrylate-b-polyethers) or copolymers
derived from these monomers, among others. One or more of these water soluble or bioresorbable
polymers may be mixed with solders of biological origin, such as those above, to change
the properties of the solder material. As a specific example, PLGA can be mixed with
albumin to increase the flexibility of the albumin solder.
[0037] In some embodiments, at least one energy absorber is used within the solder material
to enhance heating efficiency and/or heat distribution within the solder material.
Energy absorbers include chromophores, for example, light-specific dyes such as indocyanine
green (ICG), fluorescein, basic fuchsin, and fen, nano-metals such as nano-gold (e.g.,
gold nanorods, gold nanoshells, gold nanocages, etc.) and SPIONs (superparamagnetic
iron oxide nanoparticles), among other materials. Specific examples include ICG-doped
albumin, fluorescein-dye-doped albumin, and nano-gold-doped albumin, among many others.
Metal (e.g., gold, etc.) or semiconductor nanoparticles, including rods, nanoshells,
and other shapes, may be included in the solder material and heated by excitation
at their plasmon frequencies. For further information, see, e.g.,
Alexander O. Govorov et al, "Generating heat with metal nanoparticles," Nano Today,
Volume 2, Issue 1, February 2007, Pages 30-38.
[0038] Photochemical tissue bonding processes are known the surgical art. These processes
take advantage of the photochemical reactions that occur at intimately associated
tissue surfaces, which are stained with a photosensitizing dye (e.g., dyed tissue
surfaces which are placed in contact with one another). Without wishing to be bound
by theory, it is believed that the dye absorbs photons of visible radiation and promotes
the formation of covalent bonds between molecules on the approximated tissue surfaces.
For example, reactive species that are produced upon light activation of the dye can
react with potential electron donors and acceptors such as amino acids in proteins
(e.g., tryptophan, tyrosine, cysteine, and so forth). In this regard, photochemical
methods have been reported to form crosslinks in collagen type I molecules. See,
Barbara P. Chan et al., Journal of Surgical Research 108, 77-84 (2002).
[0039] In certain aspects of the present disclosure, photosensitizing dyes are used to bond
stent-containing devices to tissue surfaces, for example, by the application of light
of a suitable wavelength to a photosensitizing dye and a solder material (e.g., a
biological solder material, including those set forth above, among others) in intimate
association with a stent-containing device and a tissue surface (e.g., a photosensitizing
dye admixed with a solder material or coated on a surface of a solder material that
is in contact with and disposed between a stent-containing device and tissue), such
that the stent-containing device is bonded to the tissue. A light-emitting energy
source such as a low-power laser or light-emitting diode (LED) may be used for this
purpose, among others.
[0040] Specific examples of photosensitizing dyes include xanthene dyes such as rose bengal,
methylene blue and fluorescein, riboflavin dye (e.g., riboflavin-5-phosphate), lumichrome
dye, lumiflavin dye, Reactive Black 5, thiazine dye, naphthalimides (e.g., 1,8-naphthalimide),
erythrosine, N-hydroxypyridine-2-(1H)-thione (N-HTP), protoporphyrin I through protoporphyrin
IX, coproporphyrins, uroporphyrins, mesoporphyrins, hematoporphyrins and sapphyrins,
chlorophylis, e.g., bacteriochlorophyll A, Photofrin
®, synthetic diporphyrins and dichlorins, phthalocyanines with or without metal substituents,
chloroaluminum phthalocyanine with or without varying substituents, O-substituted
tetraphenyl porphyrins, 3,1-meso tetrakis (o-propionamido phenyl) porphyrin, verdins,
purpurins, tin and zinc derivatives of octaethylpurpurin, etiopurpurin, hydroporphyrins,
bacteriochlorins of the tetra(hydroxyphenyl) porphyrin series (e.g., protoporphyrin
I through protoporphyrin IX, coproporphyrins, uroporphyrins, mesoporphyrins, hematoporphyrins
and sapphyrins), chlorins, chlorin e6, mono-1-aspartyl derivative of chlorin e6, di-1-aspartyl
derivative of chlorin e6, tin(IV) chlorin e6, meta-tetrahydroxphenylchlorin, benzoporphyrin
derivatives, benzoporphyrin monoacid derivatives, tetracyanoethylene adducts of benzoporphyrin,
dimethyl acetylenedicarboxylate adducts of benzoporphyrin, Diels-Adler adducts, monoacid
ring "a" derivative of benzoporphyrin, sulfonated aluminum PC, sulfonated AlPc, disulfonated,
tetrasulfonated derivative, sulfonated aluminum naphthalocyanines, naphthalocyanines
with or without metal substituents and with or without varying substituents, chlorophylis,
bacteriochlorophyll A, anthracenediones, anthrapyrazoles, aminoanthraquinone, phenoxazine
dyes, phenothiazine derivatives, chalcogenapyrylium dyes, cationic selena and tellurapyrylium
derivatives, ring-substituted cationic PC, pheophorbide derivative, naturally occurring
porphyrins, hematoporphyrin, ALA-induced protoporphyrin IX, endogenous metabolic precursors,
5-aminolevulinic acid, benzonaphthoporphyrazines, cationic imminium salts, tetracyclines,
lutetium texaphyrin, texaphyrin, tin-etio-purpurin, porphycenes, benzophenothiazinium,
eosin, erythrosin, cyanines, merocyanine 540, selenium substitued cyanines, flavins,
riboflavin, proflavin, quinones, anthraquinones, benzoquinones, naphthaldiimides,
victoria blue, toluidine blue, dianthroquinones (e.g., hypericin), fullerenes, rhodamines
and photosensitive derivatives thereof.
[0041] An advantage of using light rather than heat is that there is less risk of causing
damage to the tissue (cell death) from heat. Another advantage of using light, rather
than heat, to achieve device-to-tissue bonding is that complications due to uneven
heat distribution can be reduced or eliminated.
[0042] In addition, the use of wavelength-specific absorbers such as chromophores enables
differential absorption between the chromophore-containing regions and surrounding
tissue. One advantage is a selective absorption of radiation by the target, without
the need for a precise focusing. Moreover, lower power levels may be used because
of the increased absorption of chromophore-containing regions, leading to reduced
tissue damage.
[0043] Stent-containing devices include self-expanding and balloon-expandable devices. The
stent component of the stent-containing device may be metallic or polymeric, biostable
or biodegradable. In certain embodiments, the stent component is formed from a metal
selected from stainless steel, nitinol, titanium and Elgiloy (an alloy comprising
cobalt, chromium and nickel), among others. In certain other embodiments, the stent
portion is formed from a biodegradable polymer selected from polylactide, polyglycolide,
poly(lactide-co-glycolide), polycaprolactone, and polydioxanone, among others. In
certain additional embodiments, the stent portion is formed from a biodegradable metal
such as iron, iron alloy, magnesium and magnesium alloy, among others.
[0044] The stent struts can be coated with a coating material that does not span the cells
between the struts (coated stent). The stent struts can be covered by a covering material
that spans the cells between the stent struts (covered stent).
[0045] As previously indicated, stent-containing device materials for use in accordance
with the present disclosure include bare stents, drug eluting stents (which may have
a drug eluting coating), and stents that are partially or completely covered by a
covering material. Covering materials include non-porous covering materials (e.g.,
solid films) and porous covering materials, including porous films (e.g., expanded
polytetrafluoroethylene, or ePTFE) and fiber based coverings. In this regard, stent
coverings for use in the present disclosure may be formed using a variety of fiber-based
construction techniques and include, for example, woven stent coverings and nonwoven
stent coverings (e.g., knitted, braided, coiled, randomly wrapped, spunbound, etc.).
[0046] Covering materials may be selected from various synthetic and natural polymers. Beneficial
polymers for forming coverings for stent-containing devices may be selected from the
following, among others: (a) polysiloxanes (i.e., silicones), including polydimethylsiloxane
(PDMS), among others, (b) fluoropolymers, including homopolymers and copolymers of
C2-C8 alkenes in which one or more hydrogen atoms are substituted with fluorine, for
example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), poly(vinylidene
fluoride-co-hexafluoropropene) (PVDF-HFP), among others, (c) polyamides such as nylons,
among others, (d) polyesters, including, for example, polyethylene terephthalate,
among others, (e) polyurethanes such as polyether-based polyurethanes, polycarbonate-based
polyurethanes, and polyalkene-based polyurethanes (e.g., polyisobutylene-based polyurethanes),
among others, (f) polyolefin homopolymers and copolymers, including homopolymers and
copolymers of C2-C8 alkenes, for example, polyethylene and polypropylene, among others,
(g) polyoxyalkylenes including homopolymers of trioxane (e.g., polytrioxane, also
known as polyoxymethylene or acetal) and copolymers of trioxane (e.g., copolymers
of trioxane and dioxane), and (h) styrenic copolymers such as alkene-styrene copolymers,
including block copolymers comprising one or more polystyrene blocks and one or more
polyalkene blocks, for instance, poly(styrene-
b-isobutylene-
b-styrene) (SIBS) or poly(styrene-
b-ethylene/butylene-
b-styrene) (SEBS), among others.
[0047] The fiber width (e.g., the diameter of a circular fiber) in a fiber-based stent coverings
may vary widely. In certain embodiments, the stent-containing devices of the present
disclosure may have fiber widths ranging from 1 µm to 500 µm (for example, ranging
from 1 µm to 2.5 µm to 5 µm to 10 µm to 25 µm to 50 µm to 100 µm to 250 µm to 500
µm) (i.e., ranging between any two of the preceding numerical values), among other
values. In certain embodiments, fibers may be provided with surface features, for
example, to increase the surface area of the fibers and thus the contact area between
the fibers and a bonding material coating.
[0048] Porous stent coverings in accordance with the present disclosure may also have a
wide range of pore sizes. In various embodiments, the stent-containing devices of
the present disclosure may have area pore sizes ranging from 1 µm to 100 µm (for example,
ranging from 1 µm to 2.5 µm to 5 µm to 10 µm to 25 µm to 50 µm to 100 µm) (i.e., ranging
between any two of the preceding numerical values).
[0049] Bonding material may be associated with a stent-containing device in various ways.
For example, bonding material may be applied as a coating on all or a portion of a
bare stent component, applied as a coating on all or a portion of a coated stent (e.g.,
a drug-eluting stent), or applied as a coating on all or a portion of a partially
or fully covered stent. As another example, bonding material may be admixed with impregnated
into all or a portion of a stent component material (particularly a polymeric stent
material), admixed with impregnated into all or a portion of a stent coating material,
admixed with impregnated into all or a portion of a stent covering material, or a
combination of the foregoing. As another example, a layer (e.g., a sheet) of bonding
material may be laminated onto all or a portion of a stent component material, laminated
onto all or a portion of a stent coating material, laminated onto all or a portion
of a stent covering material, or a combination of the foregoing. A stent covering
material may be coated, impregnated, and/or laminated with a bonding material either
before or after the stent covering material is associated with the stent component.
[0050] The bonding material may be present, for example, over the entire length of the stent-containing
device or only at certain points along the length of the stent-containing device,
for instance, associated with the ends of the stent-containing device. This allows
potions of the stent-containing device to be largely free of bonding material, which
reduces bonding material consumption, among other advantages.
[0051] Bonding material may be impregnated into and/or coated onto another material using
various techniques which may be selected, for example, from dipping techniques, spraying
techniques, spin coating techniques, web coating techniques, electrostatic techniques,
techniques in which bonding material is selectively applied to certain regions of
the stent-containing device but not others, for example, through the use of a suitable
application device such as a sprayer, brush, roller, pen, or printer (e.g., screen
printing device, ink jet printer, etc.).
[0052] If the bonding material does not adhere to the stent, the (optional) covering material,
or both, an intermediate layer that bonds to (a) the bonding material and (b) the
stent, the (optional) covering material, or both, may be used, for example, as a tie
layer. In certain embodiments, the intermediate layer may be transparent to the energy
that is applied to the bonding material.
[0053] As previously indicated, various embodiments of the present disclosure pertain to
stent-containing devices in which the stent component may be, for example, metallic
or polymeric, biostable or bioresorbable, self-expanding or balloon expandable.
[0054] In some embodiments, a stent component may be formed entirely of bonding material.
[0055] In some embodiments, a stent component is partially or fully coated or impregnated
with bonding material.
[0056] In some embodiments, the bonding material may be bioresorbable, for example, leaving
nothing but the stent component and/or optional covering material behind after integration
(e.g., where the stent or optional covering material is biostable or bioresorbable).
As noted above, the rate of bioresorption may be adjusted, for example, from days
to weeks to months.
[0057] In some embodiments, the stent component elements (e.g., stent wire, stent struts,
etc.) can be coated in bonding material, leaving the cells open. One specific embodiment
is shown in Fig. 1, which shows a stent 100, whose structural elements are completely
coated with a bonding material 120, but in which the stent cells 110c are left open.
[0058] In other embodiments, the bonding material may cover the stent cells. A specific
embodiment is shown in Fig. 2, which is a schematic illustration of a stent 100, whose
stent cells are covered with bonding material 120. The bonding material may be, for
example, only on the outer (abluminal) surface of the structural elements 110, only
on the inner (luminal) surface of the structural elements 110, or may completely enclose
the structural elements 110.
[0059] In some embodiments, the stent is partially coated or impregnated with bonding material.
A specific embodiment is schematically shown in Fig. 3, which shows a stent 100, wherein
the bonding material 120 is applied to structural elements 110 only at the ends of
the stent. Another specific embodiment is schematically shown in Fig. 4, wherein the
bonding material 120 is applied to structural elements 110 at intervals along the
length of the stent 100. In the embodiments shown in Figs. 3 and 4, bonding material
120 spans at least portions of the stent cells. The bonding material 120 may be, for
example, only on the outer (abluminal) surface of the structural elements 110, only
on the inner (luminal) surface of the structural elements 110, or may completely enclose
the structural elements 110. In other embodiments, the structural elements are coated
with bonding material, leaving the stent cells open.
[0060] In some embodiments, stent-containing devices are provided wherein a stent component
is partially or fully covered with a covering material. As elsewhere, the stent component
may be metallic or polymeric, biostable or bioresorbable, self-expanding or balloon
expandable. The covering material may be biostable or bioresorbable, porous or non-porous.
The covering material may be a woven or nonwoven fibrous construct. The covering material
may fully or partially cover the stent component.
[0061] A partially or fully covered stent may, in turn, be partially or fully coated with
a bonding material. For example, a partially or fully covered stent may be coated
with a bonding material on the outside (abluminal) surface, but not the inside (luminal)
surface. A partially or fully covered stent may be coated with bonding material at
or near the ends of the stent, or in any other strategic areas. A partially or fully
covered stent may be coated with bonding material on the covering but not on the stent
component.
[0062] A specific embodiment is schematically shown in Fig. 5A, wherein only the central
area of the stent portion is covered in a covering material 130. Bonding material
120 is applied to structural elements 110 at the ends of the stent in the areas that
are not covered in the covering material 130. In the embodiment shown, bonding material
120 spans the stent cells, in which case the bonding material 120 may be present,
for example, only on the outer (abluminal) surface of the structural elements 110,
only on the inner (luminal) surface of the structural elements 110, or may completely
enclose the structural elements 110. In other embodiments, the structural elements
are coated with bonding material, leaving the stent cells open.
[0063] Another specific embodiment is schematically shown in Fig. 5B, wherein the entire
stent is covered in a covering material 130 and bonding material 120 is applied to
the covering material at the ends of the stent. In certain embodiments, the covering
material may be made of a material that is transparent to the bonding energy that
is applied, such that bonding energy from an energy source positioned luminally relative
to the covering material (i.e., inside the stent) can reach bonding material on the
outer (abluminal) surface of the covering material. If an intermediate layer (not
shown) is disposed between the bonding material 120 and the covering material 130,
the intermediate material may be made of a material that is transparent to the bonding
energy that is applied as well.
[0064] In certain embodiments, for example, as shown in Fig. 6, the covering material 130
may be have openings of varying size to allow the energy to pass through covering
and activate the bonding material 120. The bonding material 120 may span the holes
as shown, and may also be applied to all or a portion of the covering material 130
in some embodiments. In some embodiments, the structural elements 110 are coated with
bonding material, but the stent cells are left open.
[0065] In some embodiments, bonding material is applied to the site independently of the
stent-containing device, in which case the stent-containing device either may be associated
with bonding material at the time of delivery (see, e.g., Figs. 1-6) or may be free
of bonding material at the time of delivery. In these embodiments, the bonding material
may be applied to tissue followed by delivery of the stent-containing device, or the
stent-containing device may be delivered followed by application of the bonding material.
After introduction of the device and bonding material, the device and bonding material
are irradiated using a suitable energy source.
[0066] The independently applied bonding material may be applied in solid form, fluid form
or a combination thereof. Where independently deposited in solid form, the bonding
material may be, for example, in the form of a patch or in a film or tape mounted
onto a device suitable for radial expansion (e.g., a balloon) that can be pressed
against a lumen wall by expanding the device (e.g., by inflating the balloon). Where
independently deposited the form of a fluid, the bonding material may be, for example,
in the form of a liquid, paste or gel (e.g., an organic or aqueous liquid, paste or
gel comprising a solider material and/or photosensitizing dye), which is deposited
using a suitable device such as a catheter. For example, the bonding material may
be applied via a catheter to a body lumen prior to deployment of the stent-containing
device or the bonding material may be deposited onto the stent-containing device after
deployment via a catheter. The bonding material and stent-containing device are then
irradiated via a suitable energy source, for example, using an energy source integrated
into the depositing catheter or another means.
[0067] In certain embodiments, bonding material may be applied to a body lumen without implanting
a stent-containing device. Where deposited in the solid form, the bonding material
may be, for example, in the form of a patch or in a film or tape mounted onto a device
suitable for radial expansion. Once pressed against the lumen wall, the bonding material
may then be welded to the wall by exposing it to energy. This may be used, for example,
to repair and/or seal tears in the lumen. In other embodiments, a bonding material
in fluid form may be used to repair and/or seal tears in the lumen.
[0068] As previously noted, a variety of energy sources may be employed in the present disclosure.
In some embodiments, the energy source is provided in conjunction with its own independent
device, whereas in other embodiments, the energy source may integrated into a delivery
device. In various embodiments, the energy source is adapted to radially direct energy
outward from the side of the device. In certain cases, the energy source is rotatable
(e.g., manually or mechanically), allowing energy to be directed in a full circle
(i.e., 360° irradiation). Full circle irradiation may be also achieved, for example,
by directing energy from around the entire circumference of the device (e.g., by means
of multiple LED's, multiple optical fibers, etc.). In certain embodiments, energy
is directed from the energy source through a transparent material, for example, a
transparent hollow catheter shaft or a transparent balloon, among other possibilities.
[0069] In embodiments where the energy source is provided in conjunction with its own independent
device, the energy source may be, for example, integrated into an over-the-wire or
monorail catheter, or the energy source may also be inserted, for example, through
a lumen in a delivery catheter. In one embodiment, illustrated in Fig. 10, a light
emitting device 340 may be provided with multiple light emitting elements 340e, for
example, multiple LEDs or fiber optic termini, which radiate outwardly from the device.
[0070] As an example of an embodiment where the energy source is integrated into a delivery
device, the energy source may be integrated into a guide wire 345 as shown in Fig.
11, for instance, by using providing a guide wire with a light emitting fiber optic
core 345e. Light from the core may be radially dispersed at the point where the light
emerges from the core using a suitable optical element. In certain other embodiments,
the energy course is integrated into a delivery catheter. For example, the delivery
catheter may be provided with multiple LEDs or fiber optic termini which radiate outwardly
from the delivery catheter. In some embodiments, an energy source is provided in conjunction
with a balloon catheter, in which case an energy source 360e may be mounted distal
to the balloon 365 of the balloon catheter 360 as shown in Fig. 12. The energy source
may also be positioned proximal to the balloon or within the balloon. If positioned
within the balloon, the balloon is made from a material that is transparent to the
energy being irradiated. An advantage in providing the energy source within a balloon,
is that the balloon helps to keep the energy source centered in the body lumen. Of
course, mechanisms other than a balloon can be used to center the energy source, such
as a delivery sheath or a stent.
[0071] An embodiment of a procedure for delivering a stent in accordance with the present
disclosure will now be described in conjunction with Figs. 7A-7C. Initially, a guide
wire 310 is positioned in a body lumen 200 as shown in Fig. 7A. Then a stent is delivered
over the guide wire 310. For example, a stent may be delivered using a delivery device
as known in the stent delivery art, for example, a device in which the stent is positioned
between an outer catheter sheath 330 and an inner catheter member 320 and delivered
to a delivery site whereupon the sheath 330 retracted, leading to self-expansion of
the stent as shown in Fig. 7B. Unlike other known procedures, however, the stent in
the present embodiment is one in which the stent elements 110 are coated with a bonding
material 120 at the ends of the stent. In the embodiment shown, after the stent is
delivered, the delivery catheter is withdrawn and a device 340 with an energy emitting
element 340e is introduced over the guide wire 310, allowing the bonding material
120 to be activated and the stent to be fixed to the tissue of the body lumen 200.
In other embodiments, an energy source may be included in the delivery catheter.
[0072] Another embodiment of a procedure for delivering a stent in accordance with the present
disclosure will now be described in conjunction with Figs. 8A-8C. In this embodiment,
a first catheter 350 having a first balloon 355 is positioned in a body lumen 200
as shown in Fig. 8A, blocking flow within the body lumen 200, which may be, for example,
a blood vessel. Then a stent 100 is delivered to the site, loaded on a second catheter
360 that is advanced over the first catheter 350 as shown in Fig. 8B. In the embodiment
shown, the entire length of the stent 100 is provided with bonding material. As seen
in Fig. 8C, the second catheter 360 has a second balloon 365 which expands the stent
100 in the body lumen 200 upon inflation. After stent expansion, an energy source
within the balloon 365 of the second catheter 360 may be used to activate the bonding
material in the stent 100, allowing the stent to be fixed to tissue of the body lumen
200. In other embodiments, the energy source is introduced via a separate device.
[0073] Yet another embodiment of a procedure for delivering a stent in accordance with the
present disclosure will now be described in conjunction with Fig. 9. In this embodiment
a self-expanding or balloon expandable stent having stent elements 110 and a stent
covering 130 is delivered to a body lumen 200 using a suitable delivery technique
(e.g., via a catheter with a retractable sheath, a balloon catheter, etc.). Subsequently,
a catheter 370 is used to deliver bonding material to the stent. For example, as shown
in Fig. 9, bonding material 120 may be delivered in liquid form from one or more lumens
3701 in the delivery catheter 370. After application of the bonding material 120,
the stent and tissue are illuminated via a suitable energy source 370e, which is supplied
on the catheter 370 in this embodiment, thereby activating the bonding material 120
such that the stent is bonded to the tissue of the body lumen 200. In other embodiments,
the energy source is inserted via a separate device.
[0074] In certain embodiments, the stent-containing devices of the present disclosure may
comprise various additional agents, including therapeutic agents and imaging agents,
among other possible agents. Such agents may be included, for example, in a coating
on or incorporated into all or a portion of the stent component material, in a coating
on or incorporated into all or a portion of the bonding material and/or as a coating
on or incorporated into all or a portion of the optional covering material.
[0075] "Therapeutic agents," drugs," "bioactive agents" "pharmaceuticals," "pharmaceutically
active agents" and other related terms may be used interchangeably herein. Therapeutic
agents include anti-restenosis, anti-hyperplasic and anti-granulation tissue agents.
Therapeutic agents may be used singly or in combination.
[0076] Additional agents for use in conjunction with the stent-containing devices of the
present disclosure also include imaging agents including (a) contrast agents for use
in connection with x-ray fluoroscopy, including metals, metal salts and oxides (particularly
bismuth salts and oxides), and iodinated compounds, among others, (b) contrast agents
for use in conjunction with ultrasound imaging, including organic and inorganic echogenic
particles (i.e., particles that result in an increase in the reflected ultrasonic
energy) or organic and inorganic echo lucent particles (i.e., particles that result
in a decrease in the reflected ultrasonic energy), and (c) contrast agents for use
in conjunction with magnetic resonance imaging (MRI), including contrast agents that
contain elements with relatively large magnetic moment such as God(III), MN(II), Fe(III)
and compounds (including chelates) containing the same, such as gadolinium ion chelated
with diethylenetriaminepentaacetic acid.
[0077] In various embodiments, the stent-containing devices may contain from less than 1
wt% to 50 wt% or more of one or more of the preceding additional agents.
[0078] In another aspect of the disclosure, medical kits useful in stent-containing device
procedures are provided. The medical kits may include all or a subset of all the components
useful for performing the procedures. For example, the medical kits may comprise any
combination of any two, three, four, or more of the following items: (a) a stent-containing
device, either without or with an associated bonding material, (b) a bonding material,
for example, in fluid form or solid form, (c) one or more medical devices (e.g., a
guide wire, a stent delivery device, and/or a device that is used to apply bonding
material), (d) an energy source (e.g., in a stand-along unit or associated with a
surgical instrument), (e) suitable packaging material, and (f) printed material with
one or more of the following: (i) storage information and (ii) instructions regarding
how to implant the stent-containing device in a subject.
[0079] Although various embodiments are specifically illustrated and described herein, it
will be appreciated that modifications and variations of the present disclosure are
covered by the above teachings and are within the purview of the appended claims without
departing from the spirit and intended scope of the invention.
[0080] The following items are preferred embodiments of the invention.
- 1. A medical device comprising (a) a stent component, (b) an optional covering material,
and (c) a bonding material associated with the stent component, the optional covering
material, or both; wherein the medical device is configured to bond to tissue when
the bonding material is exposed to an energy source.
- 2. The medical device of item 1, wherein the bonding material comprises a tissue solder
material, or wherein the bonding material comprises a tissue solder and a photosensitizing
dye, or wherein the bonding material comprises a tissue solder and an energy absorber.
- 3. The medical device of any of items 1-2, wherein the bonding material comprises
a tissue solder selected from chitosan, albumin, collagen, elastin, fibrinogen, nano-peptides,
derivatives of the foregoing, and combinations of two or more of the foregoing.
- 4. The medical device of any of items 1-3, wherein the bonding material comprises
a tissue solder and a photosensitizing dye, the photosensitizing dye being selected
from rose bengal dye, methylene blue dye, fluorescein dye, indocyanine green, basic
fuchsin, fen, xanthane dye, riboflavin dye, lumichrome dye, flavin, lumiflavin dye,
Reactive Black 5 dye, and combinations of two or more of the foregoing.
- 5. The medical device of any of items 1-3, wherein the bonding material comprises
a tissue solder and an energy absorber, the energy absorber being selected from chromophores,
superparamagnetic iron oxide nanoparticles (SPIONs), gold nanorods, gold nanoshells,
gold nanocages and combinations of two or more of the foregoing.
- 6. The medical device of item 1, wherein the bonding material comprises a tissue solder
and a synthetic polymer, the synthetic polymer being selected from polylactic acid,
polyglycolic acid, poly(lactic acid-co-glycolic acid), polydioxanone, polycaprolactone,
and combinations of two or more of the foregoing.
- 7. The medical device of any of items 1-6, wherein the bonding material is associated
with the medical device (a) by a coating of the bonding material over at least a portion
of the stent component, the optional covering material, or both, (b) by integrating
the bonding material into at least a portion of the stent component, the optional
covering material, or both, or (c) a combination of (a) and (b).
- 8. The medical device of item 7, wherein the bonding material is associated with ends
of the medical device but not the center of the medical device or wherein the bonding
material is provided as a series of bands or islands along the length of the medical
device.
- 9. The medical device of any of items 1-8, wherein the medical device comprises said
covering material.
- 10. The medical device of item 9, wherein the covering material covers only a portion
of the stent component, and wherein bonding material is associated with the stent
component in areas of the stent component not covered by the covering material.
- 11. The medical device of item 9 or 10, wherein ends of the stent component are not
covered by the covering material and/or wherein the covering material is provided
with a plurality of openings that provide areas where the stent component is not covered
by the covering material.
- 12. The medical device of any of items 9-11, wherein the covering material is sufficiently
transparent to said energy such that bonding material that is positioned abluminally
relative to the covering material can be activated using an energy source positioned
luminally relative to the covering material.
- 13. The medical device of item 12, further comprising an intermediate layer disposed
between the bonding material and the covering material, wherein the intermediate layer
material is sufficiently transparent to said energy such that bonding material that
is positioned abluminally relative to the intermediate layer material can be activated
using an energy source positioned luminally relative to the intermediate layer material.
- 14. A kit comprising a combination of any two or more of the following items: (a)
a medical device comprising a stent component, an optional covering, and an optional
bonding material associated the stent component, the optional covering, or both, (b)
a bonding material in solid form or in fluid form, (c) a surgical device, either with
or without an associated energy source, that is configured to receive and place the
medical device in a subject, (d) a guide wire, either with or without an associated
energy source, or (e) a standalone energy source.
- 15. The kit of item 14, wherein the medical device comprises a bonding material associated
with the stent component.